1. Field of the Invention
This invention pertains to a fluidized bed heat treatment apparatus with submerged infrared radiation heating sources. More particularly, this invention pertains to such an apparatus having improved means for insuring uniform heat treatment of fluidized particles.
2. Description of the Prior Art
The use of fluidized bed furnaces for heat treating a product is well known. Such furnaces generate an extremely hot bed of fluidizing particles such as aluminum oxide. The furnaces can be used for both continuous processing of a product or batch processing of products.
In addition to using such apparatus for processing of products, commonly assigned and co-pending U.S. patent application Ser. No. 07/598,415, filed Oct. 16, 1990, teaches a fluidized bed apparatus where the fluidized particles are foundry sand in a reclaiming process. In such a reclaiming process, it is desirable that the fluidized particles (i.e. the sand to be reclaimed) are all properly heat treated such that the high percentage of the sand exiting the heat treatment apparatus is being properly heat treated. It is an object of the present invention to provide a fluidized bed heat treatment apparatus with enhanced uniformity of heat treatment of the fluidized particles.